Sea To Sky

Spring Conditions. Expect avalanche hazard to increase throughout the day, especially during periods of warm, sunny weather. Always keep overhead hazard at the forefront of your mind and remember that big pieces of terrain can have big consequences.

TUESDAY: Freezing level: 1500m, 10-15mm of precipitation, moderate to strong southwesterly ridgetop winds. WEDNESDAY: Freezing level: 1500m, overcast skies with chance of very light precipitation (0-5mm),  light to moderate southerly ridgetop winds. THURSDAY: Freezing level: 1900m, cloudy, light southerly ridgetop winds.

On Sunday, numerous naturally triggered loose wet and several wet slab avalanches to size 3 were reported on solar aspects at treeline and in the alpine. Additionally, there was a size 3 cornice triggered avalanche on a northeast aspect.

Cornices are large, fragile, and could trigger deep slab avalanches that run to valley bottoms. Monitoring the overnight freeze of the snow surface is very important during the spring. If the snow surface does not freeze overnight or if the crust is only a few cm thick, the effect of daytime heating and solar radiation will weaken the snowpack much more quickly than it would if there is a well frozen thick crust. This is because the crust must first melt before the sun can weaken the snowpack. Deeply buried weak layers in the mid snowpack and near the ground still have the potential to wake up and become active with a rapid warm up. While unlikely, releases on these deeply buried weak layers would result in very large avalanches. Glide cracks are widespread, active, and best avoided. Low elevation and thin snowpack areas have become isothermal, meaning the snowpack is 0 degrees Celsius throughout. An isothermal snowpack is more prone to full depth wet slab avalanches during the heat of the day, especially on steep, rocky faces.